Corydoras Catfish

Corydoras Catfish

Corydoras are peaceful, social bottom-dwelling catfish kept in groups of 6 or more, on soft sand, in a cycled tank of 20 gallons or more. They are excellent calm tankmates and clean up leftover food.

Corydoras catfish at a glance

Scientific name
Corydoras sp.
Adult size
~2.5″
Temperature
72–80°F
pH
6–7.5
Minimum tank
20 gal
Temperament
peaceful
Social
schooling — keep 6+
Reference
Wikipedia

Corydoras are small, armored, bottom-dwelling catfish from South America, and one of the most useful peaceful community fish. They potter along the substrate all day, sifting for food, and get along with almost everything.

Groups and tank size

Corydoras are social shoalers — keep 6 or more. In a group they forage and play in the open; alone they hide. A group of the common species wants a 20-gallon or larger footprint for floor space, though dwarf species like the pygmy corydoras suit a 10-gallon.

Substrate and water

Use soft sand. Corydoras feed by sifting substrate through their barbels, and sharp gravel grinds those barbels down and invites infection. They like soft to neutral, stable water around 72–80°F. Good filtration and clean substrate matter because they live at the bottom where waste settles.

Diet

They are bottom feeders, so make sure food reaches them: sinking pellets or wafers, plus frozen bloodworms and the leftovers other fish miss. They help clean up, but they are not a cleanup crew that lives on scraps alone; feed them directly.

Temperament and tankmates

Corydoras are peaceful and ignore other fish, which makes them one of the best community tankmates. Their main companions and the few fish to avoid (from our compatibility model) are listed below. They are a classic choice with a betta — see the betta fish care guide.

Compatible tankmates for Corydoras catfish

Generated from our compatibility model — temperament, fin-nipping, temperature overlap and predation. Run your exact plan in the calculator below.

Good companions:Neon tetra, Ember tetra, Cardinal tetra, Harlequin rasbora, Guppy, Endler's livebearer, Platy, Molly, Zebra danio, Pygmy corydoras, Otocinclus, Kuhli loach, Dwarf gourami, Tiger barb, Serpae tetra, Angelfish, Cherry shrimp, Nerite snail, Mystery snail.

Avoid:Betta.

Plan a Corydoras tank

Start with the centerpiece and check stocking, filtration and compatible tankmates — live.

Planning a Corydoras catfish tank. We start with your corydoras catfish and filter the list to compatible tankmates — untick to see every species (incompatible ones get flagged).

Add fish below to see your stocking level
Stocking level
Filtration

Stocking — under 85% comfortable · 85–100% full · over 100% overstocked

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    FAQ

    How many corydoras should I keep together?
    At least 6. Corydoras are social shoaling catfish that are visibly more active and confident in a group. Singles or pairs hide and do poorly.
    What tank size do corydoras need?
    20 gallons or more for a group of the common species, which gives them floor space to forage. Dwarf species like pygmy corydoras can work in 10 gallons.
    Do corydoras need sand?
    Soft sand is best. They forage by sifting substrate through their barbels, and sharp gravel wears those barbels down and causes infections.
    Are corydoras good tankmates?
    Excellent. They are peaceful, stay on the bottom, and ignore other fish, which makes them a top choice with bettas, tetras, and most community fish.
    By AquaGauge Editorial Team · reviewed against real-tank data · updated 2026-06-18.
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